How to use the exposure triangle

Having a true understanding of how your camera operates is one of the top skills you need to have as a photographer. The exposure triangle allows you to have complete autonomy of the overall image and consists of three parts: ISO, aperture and shutter speed.

If there is one thing you should take away one thing from this explainer, it is that you need to learn how to shoot in manual! Knowing how your camera works is what separates the hobbyists from the professionals. We met with Jim Reiman, Chair of Graphic Design + Photography who explains how the exposure triangle works.


ISO stands for “International Organization of Standardization,” which explains why we call it ISO. The ISO is the camera’s sensitivity to light. Your ISO ranges from as low as 100 to 10,000+ depending on the camera you are using. The lower your ISO is, the clearer your image will be. The higher your ISO, the more noise there will be.


The aperture is the opening inside the lens. The adjustable settings within your aperture are called F-Stops and can range depending on the lens you are using. Here’s a simple difference between a low and high F-Stop.

The lower the F-Stop, the bigger the aperture. A lower F-Stop will allow in more light, but will also create a shallower depth of field.

The higher the F-Stop, the smaller the aperture. A higher F-Stop will allow in less light and create a deeper depth of field.

Shutter Speed

The shutter speed is the time your shutter is open when taking a picture. It can be as short as a fraction of a second to minutes and even longer. If you are shooting a sporting event, it is best practice to shoot at a high shutter speed to can capture the clearest image. A slower shutter speed can be useful for star trails, light painting or cityscapes. A higher the shutter speed will take in less light whereas a lower shutter speed will allow more light.

Light Meter

Once you’ve selected your settings, you can make adjustments by reading your in-camera light meter. The light meter will distinguish what an underexposed image looks like as opposed to an overexposed image. It is highly recommended to reference your light meter for the most accurate read on how your subject is lit.

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